The United States will aggressively enforce its sanctions to prevent the private sector from assisting an Iranian oil tanker that is traveling through the Mediterranean and that Washington wants seized, a State Department official said on Thursday."The shipping sector is on notice that we will aggressively enforce U.S. sanctions," the official told Reuters days after warning countries not to allow the tanker to dock.

Ship tracking data has shown the ship, Adrian Darya, formerly called Grace 1, last heading toward Greece, although Greece's prime minister said it was not heading to his country.